Question

Given below is the ECG of a normal human. Which one of its components is correctly interpreted below?

• A. Peak T - Initiation of total cardiac contraction
• B. Complex QRS - One complete pulse
• C. Peak P and peak R together - Systolic and diastolic blood pressures
• D. Peak P- Initiation of left atrial contraction only

Answer 1

The correct option is B Complex QRS - One complete pulse

By counting the number of QRS complexes that occur in a given time period, one can determine the heart beat rate (pulse) of an individual. The QRS complex represents the depolarisation of the ventricles, which initiates the ventricular contraction or systole. Peak P represents the atrial depolarization which initiates the atrial contraction. Peak T represents the joint diastole or repolarisation.